saa-xc886clm Infineon Technologies Corporation, saa-xc886clm Datasheet - Page 94

• Manufacturer Part Number: saa-xc886clm
• Description: 8-bit Single Chip Microcontroller
• Manufacturer: Infineon Technologies Corporation

SAA-XC886CLM
Functional Description
3.15.1
LIN Header Transmission
LIN header transmission is only applicable in master mode. In the LIN communication,
a master task decides when and which frame is to be transferred on the bus. It also
identifies a slave task to provide the data transported by each frame. The information
needed for the handshaking between the master and slave tasks is provided by the
master task through the header portion of the frame.
The header consists of a break and synch pattern followed by an identifier. Among these
three fields, only the break pattern cannot be transmitted as a normal 8-bit UART data.
The break must contain a dominant value of 13 bits or more to ensure proper
synchronization of slave nodes.
In the LIN communication, a slave task is required to be synchronized at the beginning
of the protected identifier field of frame. For this purpose, every frame starts with a
sequence consisting of a break field followed by a synch byte field. This sequence is
unique and provides enough information for any slave task to detect the beginning of a
new frame and be synchronized at the start of the identifier field.
Upon entering LIN communication, a connection is established and the transfer speed
(baud rate) of the serial communication partner (host) is automatically synchronized in
the following steps:
STEP 1: Initialize interface for reception and timer for baud rate measurement
STEP 2: Wait for an incoming LIN frame from host
STEP 3: Synchronize the baud rate to the host
STEP 4: Enter for Master Request Frame or for Slave Response Frame
Note: Re-synchronization and setup of baud rate are always done for every Master
Request Header or Slave Response Header LIN frame.
Data Sheet
87
V1.0, 2009-09